Fuel usage is one of the major operating costs for the airline industry and, accordingly, optimizing fuel mileage performance, i.e., fuel efficiency, is a priority. Fuel efficiency can be increased during manufacture of new aircraft and include more efficient engine design, lighter design materials and improved aerodynamics, however, for aircraft that currently exist, increasing fuel efficiency has proven difficult.
Existing aircraft, using conventional techniques to increase fuel efficiency, typically fly in specified flight envelopes that depend on an aircraft's current gross weight or mass, environmental data and performance parameters, e.g., speed and altitude. Specifically, pilots adjust the aircraft's altitude and cruise speed as the mass decreases due to fuel consumption which, in turn, optimizes fuel efficiency. Optimal cruise speeds are determined according to cost schedules derived from fuel efficiency. The cost schedules have a cost index that is calculated by airlines, and balances time and fuel costs. For example, as fuel costs increase, the cost index decreases and results in lower, i.e., slower, optimal cruise speeds.
However, conventional techniques that calculate fuel mileage performance are often inaccurate due to inaccurate calculations of mass variations and environmental data assumptions. For example, flight crews typically derive a pre-flight mass for an aircraft from combinations of actual and estimated mass. This pre-flight mass is entered into a flight computer that adjusts the flight profile according to pre-programmed algorithms, which can account for weight variations, due to fuel consumption during flight. However, these pre-programmed algorithms rely upon statistical models that often result in variances between calculated and actual conditions, including mass and environmental conditions.
Other conventional techniques that attempt to calculate fuel mileage performance occur post-flight. For example, some airlines manually track fuel consumed at the end of each flight. However, this approach fails to assist optimizing fuel efficiency during flight since it only measures fuel mileage performance post-flight.
Clearly, there is a need in the art for improved systems and methods that increase fuel efficiency for aircraft, via real-time aircraft performance monitoring. Moreover, there is a need to more accurately determine the mass using real-time aircraft performance monitoring, in turn, increases fuel mileage performance, e.g., fuel efficiency. Further still, there is a need to more accurately monitor other factors, in real-time, which effect fuel mileage performance, e.g., environmental conditions.